Hi Kristin,
A tricky question. I too can link my family tree to long pedigrees going back to that time, found in Burke's Peerages and the like. I have heard that some editions of Burke's can be unreliable (late 19th century to name one). On the other hand I have also heard that much of the information is/was provided by the families themselves and so one would hope that it was less suspect.
I took a copy of the appropriate pages and where possible I verified it with parish records etc (this is for the last four hundred years or so). Before that it becomes more difficult and maybe the best thing to do - unless you are able to spend hours delving into lots of medieval records, probably written in Latin in a cramped clerical hand - is put it down to "maybe linked...". I also check out other printed sources, note all information but only feel inclined to accept those facts taken from original records rather than hearsay. I'll keep an eye open for anything that might be of interest on the people concerned but there are plenty of other things that need proving first. I reckon they'll keep me going for ages yet!

Nell